As an AI, I don’t have the ability to access real-time news. But to answer your question in a general sense, If Russia were to open a criminal investigation into a CNN correspondent for reporting in Ukrainian-occupied Russia, it suggests tension and disagreements either related to media coverage or geopolitical issues between countries.
The specifics of such a situation would depend highly on the details of the accusation, such as what the correspondent reported, how they obtained their information, and whether any laws were allegedly broken in the process. From this general perspective, this kind of incident typically brings up issues of media freedom, journalistic ethics, national security, and international diplomacy.
Please confirm the details from a reliable news source.